Ventilated lighting fixture

ABSTRACT

A recessed lighting fixture having a ventilating channel positioned at one or both ends thereof. The channel is formed by plates, one having an offset portion and the other extending into the offset portion to form a tortuous path for air flowing into the fixture. The channel acts as a dust trap and prevents any light from escaping therethrough.

United States Patent [72] Inventor Ormond S. Sutter Placentia, Calif.[21] Appl. No. 667,567 {22] Filed Sept. 13, 1967 [45] Patented Jan. 12,1971 [73] Assignee bolt-Products Co.

Fullerton, Calif. a corporation of California [54] VENTILATED LIGHTINGFIXTURE 7 Claims, 6 Drawing Figs.

[52] US. Cl 240/47, 240/9, 240/51.1 1, 240/147: 98/40 [51] Int. Cl F2lv29/00 [50] Field ofSearch 240/51.11, 47, 9, 147; 98/40DL [56] ReferencesCited UNITED STATES PATENTS 3,012,133 12/1961 Archer 240/9H 3,101,0388/1963 Archer 240/47X 3,103,157 9/1963 Quin 240/51.11X 3,312,160 4/1967Rackley 240/47X 3,326,112 6/1967 Sadlow et a1... 240/47X 3 ,348,465 10/1 967 Kruger 98/4ODL 3,375,773 4/1968 Wotowiec et al 98/40DL 3,389,2496/ 1968 Rackley 240/147 Primary ExaminerJohn M. Horan AssistantExaminer-Richard M. Sheer Att0rneyLyon and Lyon ABSTRACT: A recessedlighting fixture having a ventilating channel positioned at one or bothends thereof. The channel is formed by plates, one having an offsetportion and the other extending into the offset portion to form atortuous path for air flowing into the fixture. The channel acts as adust trap and prevents any light from escaping therethrough.

VENTILATED ucrrrmc FIXTURE BACKGROUND OF THE INVENTION Recessed lightingfixtures for housing fluorescent or incandescent lamps are in almostuniversal use in industrial commercial and residential buildings. Thesefixtures generally comprise a metal housing having a flange around thebottom thereof for supporting a sheet-of light-transmitting glass orplastic which can be removed in some fashion to provide access to thelamps positioned within the housing. The housings are usually supportedby channels that are suspended from the ceiling of the building orsupported by the walls thereof, the individual lighting fixtures usuallybeing separated by acoustical tile or other suitable ceiling materialswhich are also supported by the channels.

In operation, such lighting fixtures generate appreciable amounts ofheat. If the lamps are fluorescent, the heat is generated by the ballasttransformer as well as by the lamps whereas if the lamps areincandescent, they themselves generate a large amount of heat. In thepast, although vents have sometimes been provided in the metal housings,the fixtures have not been constructed to insure that sufficientventilating air is passed through the fixture. Thus, while the spaceabove the ceiling in which the fixtures are mounted provides what is ineffect a large heat sink that is itself usually vented, the heat in thepresently available fixtures is primarily retained within the fixturecausing appreciable reduction of the average lifetime of the lamps.Moreover, such air as does enter the fixtures carries with it dust whichis deposited on the lamps or on the light-transmitting sheet, thusreducing the illumination produced.

SUMMARY OF THE INVENTION According to the present invention, a lightingfixture is provided which has a ventilating channel that providessufficient air to the interior of the fixtures such that the ambienttemperature in the fixture is less than that in conventional fixtures.

The channel is constructed in such a manner that it provides atortuouspath for the entering air and thus acts as a dust trap therebykeeping the lamps and the light-transmitting sheet or diffuser clean fora longer time than is possible with conventional fixtures. This bothincreases the illumination from the fixture and decreases the amount ofmaintenance required. The ventilating channel serves as a light shieldand thus does not reduce the aesthetic appeal of the fixture. Theventilating channel is mounted directly on the diffuser so that noseparate lens frame with its attendant hinges, slots and light shieldsis required. I

It is therefore an object of the present invention to provide aventilated lighting fixture.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an end elevational view,partly broken away and partly in section, of the lighting fixture of thepresent invention;

FIG. 2 is a sectional view taken along lines 2 2 of FIG. 3;

FIG. 3 is a sectional view taken along lines 3-3 of FIG. 2;

FIG. 4 is an exploded perspective view showing the construction of theventilating channel of the present invention;

FIG. 5 is a perspective view of one end of the ventilating channel ofthe present invention and the manner in which it is mounted; and

FIG. 6 is a detailed view showing the manner in which the lightingfixture of the present invention may be opened for access to the lampsthereof.

DESCRIPTION OF THE INVENTION Turning now to the several FIGS., there isshown the lighting fixture of the present invention. The lightingfixture 10 has a metal body or housing 11 in the upper portion of whichare formed a plurality of louvred slots 12. The interior of the fixturebody 11 is provided with an enclosure plate 13 and a transformer shield14, the transformer shield 14 enclosing a region 15 in which the ballasttransformer is positioned. As can be seen, the fixture body 11 is alsoprovided with horizontal flanges 16 (only one of which is shown) whichare supported by the horizontal flanges of the various ceiling gridmembers 17. These members also serve to support other ceiling material18, for example, acoustical tile.

A light-transmitting sheet or diffuser 19 is formed with an a upwardlyextending flange 20 having a horizontal lip 21 extending therefrom. Thelip 21 rests on the flange 16 of the fixture body 11 whereby thediffuser 19 is maintained in place. Although only one edge of thediffuser 19 is shown, the other is identical. The lamps 22, supported bymounting means 43, are positioned within the fixture body 11 below theenclosure plate 13, the latter being provided with louvred slots 42 oneither side of the transformer shield 14 to permit air to circulate fromthe interior of the fixture around the lamps 22 into the upper portionaround the transformer shield and thence out of the slots 12. The slots12 are preferably centered along the length of the fixture and extendfor a distance approximately equal to, or greater than, the length ofthe transformer shield. The slots 42 are preferably positionedimmediately below the slots 12.

At one or both of the ends of the fixture 10 there is provided aventilating channel or air entry assembly 25. This assembly comprises anair path enclosure 26, a lens end plate 27, a pair of end caps 28 and apair of retainer clips 29. The air path enclosure 26 and the lens endplate 27 are provided with tabs 30 and 31, respectively, that fit intosuitable slots in the end caps 28 and which are then folded over tounitize the structure. The end caps 28 are provided with a steppedflange 32 to fill the void between the end of the diffuser I9 and thenext transverse grid member as is shown in FIG. 5. The end cap 28 isalso provided with a slot 33 for receiving a tab 34 of the retainer clip29. As can be seen, the retainer clip 29 is provided with a hookedportion 35 which fits over the vertical flange 20 of the diffuser 19.The hooked portion 35 is preferably provided on either side with punchedtangs 36 which serve to engage the flange 20 in a springlike manner. Thelens end plate 27 is provided with a pin 37 for a purpose to bedescribed hereinafter.

As can be seen, the lens end plate 27 is provided with a I horizontalflange 38 which extends into the offset portion of the air pathenclosure 26 thus forming a tortuous path for air entering thisenclosure from below the fixture as can best be seen in FIG. 3. Theassembly 25 thus serves as a dust trap to collect the dust that wouldnormally settle on the lamps 22 or on the diffuser 19, and also serve tocreate good circulation within the body of the fixture as the airtravels from the air entry assembly to the exit slots 42 and 12. Asshown in FIG. 3, a strip of packing material 39 is preferably positionedbetween the air entry assembly 25 and the end wall 40 of the fixturebody 11 to prevent the entry of air or the exit of light.

In order to gain access to the interior of the fixture body 1 l, forexample, for the purpose of changing the lamps 22, the diffuser 19 canbe raised and slid to the left so that the right-hand side of thediffuser comes clear of the right side of the horizontal flange of thefixture body 11. The pin 37 will then rest on a horizontal flange 41 ofthe end wall 40 of the body 11 and serve as a pivot point so that thediffuser 19, together with the air entry assembly 25 mounted thereon,can be swung away from the remainder of the fixture. This is best shownin FIG. 6. Although only one air entry assembly 25 is shown, it shouldbe understood that such an assembly can be provided at each end of thefixture if desired.

From the foregoing description, it can be seen that a lighting fixturehas been provided in which ventilation is easily accomplished. Air isintroduced at either or both ends of the fixture and is circulatedtherethrough exiting at the top. The air is circulated past the lampsand past the transformer enclosure so that the heat generated from bothis dissipated. The air leaving the fixture is passed to the area abovethe ceiling where it can be collected by any suitable means, forexample, the plenum of the building air-conditioning system. As a resultof the structure of the present invention, the lamps and ballasttransformer are operated at an optimum temperature so that theefficiency and lifetime of these components is increased. Moreover, thestructure is such that dust is collected remote from the lamps anddiffuser so that their illumination is increased and the maintenancenecessary for them is decreased. In addition, the air entry enclosureassemblies are mounted directly on the diffuser and thus an integralunit is provided without the necessity of utilizing a separate lensframe which need be provided with hinges, slots with built-on lightshields and the like.

While there has been described what is at present considered a preferredembodiment of the present invention, it will be apparent to thoseskilled in the art that various modifications and changes may be madewithout departing from the essence of the invention, and it is intendedto cover herein all such modifications and changes as come within thetrue scope and spirit of the appended claims.

1 claim:

1. A lighting fixture comprising: a housing, means for mounting lamps insaid housing, a plurality of siots formed in said housing above saidlamp mounting means whereby air may exit therefrom, diffuser meansmounted on said housing, said diffuser means having an upstanding flangealong each longitudinal edge thereof, and means positioned at the end ofsaid housing for permitting air to enter said housing, said meanscomprising a first plate having an offset portion, a second plate havinga portion extending into said offset portion of said first plate wherebya tortuous path is formed, said path having a first end opening withinsaid housing and a second end opening exteriorly thereof; a pair of endplates for mounting said first and second plates, and clip means mountedon each of said end plates, said clip means being mounted on saidupstanding flanges of said diffuser means.

2. The fixture of claim I wherein said second plate is pro vided withpin means adapted to cooperate with said housing to permit said diffusermeans to be moved away from said housing. I

3. The fixture of claim 1 wherein said flanges of said diffuser meansare each provided with a horizontally extending lip, and wherein saidhousing is provided withinturnedflanges for supporting said lips of saiddiffuser means.

4. A lighting fixture comprising a housing, 'an enclosure plate withinsaid housing, means'in said housing below said closure plate formounting lamps therein; a transformer enclosure within said housing andabove saiden'closure plate, a plurality of slots formed in saidenclosure plate adjacentsaid transformer enclosure, a plurality of siotsformedin said housing above said enclosure plate whereby air may exitfrom said housing, diffuser means mounted on said housing, said diffusermeans having an upstanding flange along each, longitudinal edge thereof,and means positioned at one end of said housing for permitting air toenter said housing, said means comprising a first plate having an offsetportion, a second plate having a portion extending into said offsetportion of said first plate whereby a tortuous path is formed, saidpath'having a first end opening within said housing and a second endopening exteriorly thereof; a pair of end plates for mounting said firstand second plates, and clip means mounted on each of said end plates,said clip means being mounted on said upstanding flanges of saiddiffuser means. U I

5. The fixture of claim 4 wherein said second plate is provided with pinmeans adapted to cooperate with said housing to permit said diffusermeans to be moved away from said housing.

6. The fixture of claim 4 wherein said flanges of said diffuser meansare each provided with ahorizontally extending lip, and wherein saidhousing is provided with inturned flanges for supporting said lips ofsaid diffuser means.

7. The fixture of claim 4 wherein each of said clip means has a U-shapedportion for receiving said flange of said diffuser means, said U-shapedportion having tangs for firmly grasping said flange.

1. A lighting fixture comprising: a housing, means for mounting lamps insaid housing, a plurality of slots formed in said housing above saidlamp mounting means whereby air may exit therefrom, diffuser meansmounted on said housing, said diffuser means having an upstanding flangealong each longitudinal edge thereof, and means positioned at the end ofsaid housing for permitting air to enter said housing, said meanscomprising a first plate having an offset portion, a second plate havinga portion extending into said offset portion of said first plate wherebya tortuous path is formed, said path having a first end opening withinsaid housing and a second end opening exteriorly thereof; a pair of endplates for mounting said first and second plates, and clip means mountedon each of said end plates, said clip means being mounted on saidupstanding flanges of said diffuser means.
 2. The fixture of claim 1wherein said second plate is provided with pin means adapted tocooperate with said housing to permit said diffuser means to be movedaway from said housing.
 3. The fixture of claim 1 wherein said flangesof said diffuser means are each provided with a horizontally extendinglip, and wherein said housing is provided with inturned flanges forsupporting said lips of said diffuser means.
 4. A lighting fixturecomprising: a housing, an enclosure plate within said housing, means insaid housing below said closure plate for mounting lamps therein, atransformer enclosure within said housing and above said enclosureplate, a plurality of slots formed in said enclosure plate adjacent saidtransformer enclosure, a plurality of slots formed in said housing abovesaid enclosure plate whereby air may exit from said housing, diffusermeans mounted on said housing, said diffuser means having an upstandingflange along each longitudinal edge thereof, and means positioned at oneend of said housing for permitting air to enter said housing, said meanscomprising a first plate having an offset portion, a second plate havinga portion extending into said offset portion of said first plate wherebya tortuous path is formed, said path having a first end opening withinsaid housing and a second end opening exteriorly thereof; a pair of endplates for mounting said first and second plates, and clip means mountedon each of said end plates, said clip means being mounted on saidupstanding flanges of said diffuser means.
 5. The fixture of claim 4wherein said second plate is provided with pin means adapted tocooperate with said housing to permit said diffuser means to be movedaway from said housing.
 6. The fixture of claim 4 wherein said flangesof said diffuser means are each provided with a horizontally extendinglip, and wherein said housing is provided with inturned flanges forsupporting said lips of said diffuser means.
 7. The fixture of claim 4wherein each of said clip means has a U-shaped portion for receivingsaid flange of said diffuser means, said U-shaped portion having tangsfor firmly grasping said flange.